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HOME > FEWS-NET > Weekly Weather Summaries

Weekly Weather Summaries Archive



2001 Jan 10 Jan 18 Jan 25 Jan 31 Feb 08 Feb 14 Feb 22 Feb 28
Mar 08 Mar 15 Mar 21 Mar 29 Apr 04 Apr 11 Apr 19 Apr 25
May 02 May 09 May 16 May 23 May 30 Jun 06 Jun 13 Jun 20
Jun 27 Jul 04 Jul 11 Jul 18 Jul 25 Aug 01 Aug 08 Aug 15
Aug 22 Aug 29 Sep 06 Sep 13 Sep 20 Sep 27 Oct 04 Oct 11
Oct 18 Oct 25 Oct 31 Nov 07 Nov 14 Nov 21 Nov 28 Dec 06
Dec 13 Dec 20 Dec 27


January 10, 2001

The cold sea surface temperature of La Nina in the eastern Pacific has continued into the current winter which results in the warm surface water extended toward Indonesia. This warm surface water is associated with greater atmospheric convective activity. Therefore, the potential exists for above average number of tropical storms in the South Indian Ocean. Tropical Cyclone Ando was the first named storm of the season and passed just east of Madagascar. Tropical Cyclone Bindu was last reported near 16S, 72E and we will continue to issue bulletins on position, strength and forecast as received. As indicated previously, the CPC Homepage includes a 24-hour infrared animated loop. The web address is: www.cpc.ncep.noaa.gov/products/fews/24_hour_loop.html Area of northern Mozambique and Zambia is highlighted for potential local flooding as described. The heat over the cornbelt is included because of the POSSIBLE adverse effect on crops. Once the continental tropical airmass is replaced with a more maritime airmass (a discontinuous process on the days-weeks-months timescale), that threat will be over (should be late Friday). Since this is a discontinuous process, if there are no indications for such an episode next week, it will be removed without regard for continuity, an appropriate action for such a process on the 7-day timescale. Dryness persisted across much of Kenya and northeastern Uganda. Although Kenya and northeastern Uganda benefitted from good rains the previous 10-day period, long term dryness has persisted over much of this sub-region, where only light to moderate rains (1-40 mm; 3-70% of normal) were observed. Rainfall was also light to moderate across much of Tanzania. Light rains were also observed over much of Botswana and northern Namibia. Because of the long-term dryness in the area of Kenya, we will continue to watch carefully this situation.
January 18, 2001

Tropical Cyclone Bindu posed no threat to the African continent and has diminished in strength to the point that coverage has been dropped. A new Tropical Depression has formed, but is not yet named. We will continue to issue bulletins as received. Hot, dry weather continued in northern and central Namibia, though thunderstorms brought some relief to southern Angola on January 15-16, with some rain penetrating northern Namibia. Four-week rainfall totals through January 13 were less than 25% of normal at some locations in central and northern Namibia. Unusually warm and dry weather has covered most of southern Africa since January 2, though thunderstorms brought rains to northern Zimbabwe and parts of northern South Africa on January 15-16. If the dry pattern that includes southern Zimbabwe, Botswana, southern Mozambique, and South Africa's maize triangle continues, it may have an adverse impact on the maize crops in the region, as we are now getting into the critical growth stages for that crop. Low pressure in the Mozambique Channel is bringing heavy rains to Madagascar and northern Mozambique. Though heavy rains have caused flooding in southern Kenya, where 4-week rainfall has been more than 200% of normal, the long-term drought persists in northern Kenya. Satellite vegetation data suggests the dryness extends into southern Somalia.
January 25, 2001

Tropical Cyclone Charly is passing well to the east of the African continent and is diminishing in strength. A Tropical Depression formed just to the east of Madagascar, but this storm has moved over land and did not become cyclone strength. It has added, however, to the large rainfall totals received this year over Madagascar, over 400 mm since January 11 in some locations. The NWS extended model suggests that this storm may re-intensify over the warm water of the Mozambique channel. We will continue to monitor the situation and issue bulletins as necessary. Cyclone bulletins will be transmitted as received. In southern Africa, rainfall remained generally below normal over most areas. Scattered showers brought some dryness relief to southern Angola and northern and central Namibia, but cumulative rainfall for the season has remained well below normal. Dry conditions continued to prevail over southern Namibia and southern Botswana. Light to moderate rains fell in southern Mozambique, much of Zimbabwe and northeastern South Africa.. Torrential rains struck large areas of Madagascar, as a tropical low pressure area remained nearly stationary over the Mozambique Channel. Totals of 150 to 400 mm were common over all but the far northern and southern areas of the island, with up to 476 mm inundating the Besalampy area on the northwest coast. Heavy rains also fell over northern and eastern Zambia and into southern DRC, southern Malawi and northern Mozambique. Unseasonably heavy rains fell over southern and western coastal areas of South Africa. Temperatures were generally 1 to 2 degrees C below normal over southern Africa except 2 to 3 degrees above average in northern Namibia and northeast South Africa. In East Africa, above-normal rains covered much of Tanzania, parts of southern Uganda and southwestern Kenya. Temperatures were near average across the region. In central Africa, unseasonably heavy rains fell in western DRC and southern Congo. Temperatures generally averaged 1 to 2 degrees C below normal across the region except in Gabon, where they were 1 to 3 degrees C above average. In West Africa, the dry season continued over the Sahel and the Gulf of Guinea region. Temperatures were 1 to 3 degrees C above average except in Chad, where they averaged 1 to 3 degrees C below normal.
January 31, 2001

Please note that we have changed the area of the accompanying map to include all of Africa and Madagascar. To do this we have had to then separate the graphic from the text. They are now in two files, a and b. Tropical Cyclone Charly passed well to the east of the African continent and posed no threat to the continent. A Tropical Depression formed just to the east of Madagascar, but this storm moved over land and did not become cyclone strength. It has added, however, to the large rainfall totals received this year over Madagascar. We continue to monitor the sea surface temperature over the Pacific Ocean to determine the continuing extent and magnitude of the La Nina situation as it pertains to the likelihood of development of cyclones in the Indian Ocean along with their steering currents. Cyclone bulletins will be transmitted as received. Very heavy rains struck central and northern Mozambique in the past week and continued to plague parts of Madagascar. The area in Mozambique bearing the brunt of the torrential rains extended from near Beira in Sofala province northward along the coast to Quelimane in Zambezia province. Satellite-estimated rainfall for the 7 days through January 29 exceeded 300 mm (12 inches) in this zone, with some amounts locally exceeding 500 mm (20 inches). The area of heavy rains included the lower reaches of the Zambezi River. Heavy rains have fallen throughout northern Mozambique, with estimated weekly amounts reaching 500 mm locally in Cabo Delgado in the northeast. Beira along the central coast reported a one-day total of 106 mm on January 28 on top of 27 mm the day before. Satellite imagery indicated that heavy thunderstorms struck this area again on the 30th. In Madagascar, 7-day rainfalls exceeded 300 mm and ranged up to 500 mm in west-central areas and along the northwest coast. Locally heavy rains have also fallen in northeastern parts of the island. Heavy rains extended northward into Tanzania, southwestern Kenya, and Malawi, with 200 mm (8 inches) common in Malawi and southern Tanzania. Wet conditions expanded westward across Zambia into Angola, as locally heavy rains hit interior portions of northwestern and southwestern Angola--areas that had previously been abnormally dry. Daily showers since January 18 have benefitted the dry areas in central and northern Namibia, but very dry conditions have developed across Botswana, central and southern Zimbabwe, southern Mozambique, northern South Africa, and Swaziland. Rainfall has been light and sporadic in this region since January 2, and periods of high temperatures have aggravated the dryness. The lack of moisture coincides with the critical growth stage for maize crops in the region.
February 8, 2001

The circulation pattern appears to remain in a strong La Nina mode with neutral conditions not forecast to occur until this coming spring season. We continue to monitor the sea surface temperature over the Pacific Ocean to determine the continuing extent and magnitude of the La Nina situation as it pertains to the likelihood of development of cyclones in the Indian Ocean along with their steering currents. Cyclone bulletins will be transmitted as received. On a shorter time-scale we note that the numerical forecast models indicate a continued threat of severe localized rainfall through the coming weekend. As forecast last week, very heavy rains struck central Mozambique during February 4-6, increasing the potential for additional flooding. The rains hit some of the areas affected by heavy rains in late January, but also struck farther south, including areas that had been enduring drought. The heaviest rains fell on February 4-5, with satellite-estimated 24-hour amounts exceeding 100 mm from central Inhambane province in the south to central Zambezia province in north-central Mozambique. Heavy rains also extended westward into extreme southeastern Zimbabwe. In Mozambique, estimated totals locally exceeded 200 mm in northern Inhambane and southern Sofala. On the preceding day, thunderstorms dropped 50 mm or more over large areas of central Mozambique as well as northeast Zimbabwe. As a result, some locations in south-central Mozambique may have received as much as 300 mm of rain in 2 days. Satellite imagery on the 6th indicated that heavy showers again fell over the same area, further adding to the rainfall totals. Elsewhere, heavy rains diminished across Madagascar, Tanzania and southern Kenya, but excessive rains also struck southern Malawi near the border with Mozambique. Drought continued over extreme southern Mozambique, with only light rains falling over most of Gaza province so far this month, continuing the dry trend from January. The recent deluge ended drought across much of Inhambane province just to the north. Abnormally dry conditions persisted over south-central and southwestern Zimbabwe, as well as northern South Africa and much of Botswana.
February 14, 2001

We continue to monitor the sea surface temperature over the Pacific Ocean to determine the continuing extent and magnitude of the La Nina situation. Cyclone bulletins will be transmitted as received. On a shorter time-scale we note that the numerical forecast models indicate a continued threat of severe localized rainfall. Heavy rains continued over parts of central Mozambique following the February 4-6 deluge, though amounts were not as extreme. According to satellite rainfall estimates, the provinces of Tete, Sofala, and Zambezia have sustained the brunt of the rains since the 6th, with the heaviest rains (over 75 mm) falling on Tete province on February 6-7. Weekly rainfall totals through February 11 exceeded 150 mm across much of central Mozambique, with estimated isolated totals of 250 mm over southern Sofala. Excessive rains (over 150 mm) also fell over extreme southeastern Zimbabwe, extreme southern Malawi, south-central Angola, and scattered locations in southern and western Zambia. Rains diminished in Tanzania, Kenya, and Madagascar. Abnormal dryness persisted in Namibia, central and southern Botswana, extreme southern Mozambique, Swaziland, and much of South Africa. Four-week rainfall totals are generally under 50% of normal across this region. The recent heavy rains have nearly eliminated dryness from Zimbabwe, with only the extreme south remaining abnormally dry. To the north, the first season (belg) rains appear to have started on schedule in Ethiopia. Last year, these rains virtually failed.
February 22, 2001

We continue to monitor the sea surface temperature over the Pacific Ocean to determine the continuing extent and magnitude of the La nina situation. The atmospheric circulation remains in a La Nina state with the forecast models suggesting a possible weakening to a neutral state this Spring. Thus, for the next month we anticipate a possible continuation of the current situation with greater than normal precipitation in the region of Mozambique. On a shorter time-scale we note that the numerical forecast models indicate a continued threat of severe localized rainfall. Cyclone bulletins will be transmitted as received. Additional heavy rains fell in Mozambique's Zambezia Province during February 13-19, with satellite estimates exceeding 150 mm over interior areas adjacent to the Malawi border. Similar heavy amounts also accumulated over parts of southern Malawi. Heavy rains fell again in other parts of central Mozambique, with totals exceeding 100 mm in coastal Sofala province and in extreme northeastern inhambane in the south. Satellite estimated rainfall reaching 150 mm in Tete Province added to the excessive rainfall totals affecting Mozambique's Zambezi River Basin. Moderate to heavy rains relieved dryness across extreme southern Mozambique in Gaza and Maputo. Elsewhere in southern Africa, increased rainfall benefited dry areas across Namibia, Botswana, South Africa, and southern Zimbabwe. In particular, heavy showers (25-75 mm) alleviated dryness in extreme northern South Africa and adjacent Zimbabwe on February 20. Despite some recent rainfall, abnormally dry conditions have persisted since the start of the year in much of Botswana, northeastern Namibia, and part of South Africa's maize triangle.
February 28, 2001

The Pacific Ocean sea surface temperature remains in a relatively weak La Nina situation and the forecast models suggest a possible weakening to a neutral state this April. Although the tropical cyclone threat has been very low over the past several weeks, we continue to monitor the situation and bulletins will be transmitted as received. Heavy rains tapered off during the past week in the flood-affected areas of Mozambique, with estimated amounts during February 20-26 mainly in the 10 to 75-mm range. This contrasts with the 75 to 200 mm that accumulated during the preceding week. Rainfall also dropped off in Malawi, Zambia, and Zimbabwe. Nevertheless, estimated rainfall amounts locally topped 75 mm in Mozambique's Tete and Zambezia provinces, as well as in south-central Zambia and west-central Zimbabwe. Satellite imagery on February 27 shows the return of heavy thunderstorms to southern Malawi and adjacent portions of Mozambique's Zambezia province. In the areas that had been earlier abnormally dry, increased rainfall continued to add to soil moisture, with amounts of 10 to 75 mm across much of Namibia, Botswana, and the summer crop areas of South Africa. In East Africa, long-term drought continued across Kenya's pastoral areas and adjacent portions of Ethiopia, Uganda and Sudan.
March 8, 2001

The Pacific Ocean sea surface temperature remains in a La Nina situation and the forecast models suggest a possible weakening to a neutral state this May-June. A tropical depression has formed over the northern Mozambique Channel and is currently moving south-southwest. This disturbance may intensify in the next 48 hours and poses a threat to eastern Mozambique and western Madagascar. We continue to monitor the situation and bulletins will be transmitted as received. A tropical disturbance in the Mozambique Channel was bringing heavy thunderstorms to northeast Mozambique and the Comoro Islands on March 6-7, according to satellite imagery and the latest rainfall reports. Six-hour rainfall totals on March 7 totaled as high as 91 mm in the Comoros. On March 8, the disturbance was located just off the coast of the Nampula Province in Madagascar, based on the latest report from the Joint Typhoon Warning Center. Potential for development was rated as good. The heaviest rains so far have been mainly north of the ares in Mozambique affected by the January-February rainfall and flooding. The current rains have been striking the provinces of Cabo Delgado and Nampula. For the week ending March 5, totals were seasonably heavy across Mozambique, although satellite estimates indicated that locally heavy amounts (75-100mm) continued over the central provinces, including Sofala, Manica, Tete, and interior Zambezia. Locally heavy rains also persisted over southern Malawi and central and western Zambia. Widespread rains of 75-125 mm covered central and northern Zimbabwe.
March 15, 2001

It is likely that cold episode Pacific sea surface conditions will gradually weaken over the next several months, with near-normal conditions likely during the summer of 2001. This assessment is generally supported by the most recent NCEP statistical and coupled model forecasts, as well as by other available coupled model and statistical model predictions, which indicate a gradual weakening of cold episode conditions during the next few months. Thereafter, the models indicate near-normal or slightly warmer-than-normal conditions during the second half of 2001. Tropical Cyclone Dera affected the Mozambique Channel, western Madagascar, and eastern Mozambique from March 7-12. Intensifying to cyclone strength as it approached the center of the channel, Dera spared most flood ravaged areas of Mozambique, but did produce heavy rains over the northeast provinces and southwestern Madagascar. 24 hour precipitation totals on March 8th approached 100 mm in the provinces of Niassa, Cabo Delgado, Nampula, and northern Zambezia of Mozambique. Up to 50 mm of rain fell over southwest Madagascar on March 10 as the cyclone exited the region. Weekly rainfall totals from March 6-12 locally exceeded 150 mm in northeast Mozambique and exceeded 100 mm in southwestern areas of Madagascar. The winter crop belt region of Morocco received some relief, with locally 15 mm weekly precipitation totals. The drought affected area of southern Ethiopia received regional precipitation amounts exceeding 50 mm, but northern Kenya remains quite dry. As expected, rainfall has begun in southern areas of west Africa, with weekly totals exceeding 50 mm in parts of Cote d'Ivoire and Ghana.
March 21, 2001

Since early February 2001, SSTs have become anomalously warm in many sections of the eastern tropical Pacific with a gradual expansion of the area of positive equatorial subsurface temperature anomalies into the central Pacific. This evolution is consistent with a slow decay of the subsurface thermal structure that characterizes the mature phase of cold episodes. Thus, it is likely that cold episode conditions will gradually weaken over the next several months, with near-normal conditions likely during the summer of 2001. This assessment is generally supported by the most recent NCEP statistical and coupled model forecasts, as well as by other available coupled model and statistical model predictions, which indicate a gradual weakening of cold episode conditions during the next few months. Thereafter, the models indicate near-normal or slightly warmer-than-normal conditions during the second half of 2001. Areas hit by heavy rains in northeastern Mozambique during the preceding week recorded lighter amounts during the week ending March 19, with totals mostly under 50 mm. However, rainfall tended to remain above normal from Mozambique to Zambia, with locally heavy rains exceeding 75 mm in Tete province in northwest Mozambique and various locations in the south. Estimated totals exceeded 150 mm along the southern coast of Mozambique's Inhambane province. Amounts also exceeded 75 mm in extreme southern Malawi and in isolated locations in northern and eastern Zimbabwe and central Zambia. Northern Tanzania continued quite dry, while long-term drought persisted in northern Kenya. Short-term dryness has developed to the south. Four-week rainfall totals are under 50% of normal in central and southern Kenya, where the main rainy season is normally progressing. Seasonal rains fell over central, northern, and western Ethiopia. The seasonal rains in West Africa continued to slowly advance northward along the Gulf of Guinea coast, but amounts remained below normal in southern parts of Togo, Benin, and Nigeria. There was little or no rain in Morocco, where chronic dryness has affected southern wheat areas this season. Below-normal rain also prevailed in Algeria and Tunisia, with rainfall generally less than one-half normal in the past 4 weeks. High temperatures worsened the dryness in northern Africa.
March 29, 2001

An area of storminess has been noted at about 10S, 80E. While this area has been posted as having a poor chance to magnify into an actual cyclone, the NWS forecast models are forecasting it to migrate westward toward northern Madagascar and Mozambique. The potential exists for significant rainfall from this system during the early part of next week. We will maintain watch on this system as it moves and develops, providing bulletins as necessary. Rains continued to diminish in central Mozambique, including the flood-affected Zambezi River basin, with weekly rainfall totals through March 26 generally under 50 mm. Most of southern Mozambique recorded less than 10 mm of rain. Isolated rainfall totals did exceed 75 mm locally along the central Mozambique coast in northern Sofala and southern Zambezia. Beneficially drier weather, with rainfall amounts mostly under 50 mm, also covered southern Malawi, southern Zambia, and most of Zimbabwe. In East Africa, rainfall increased, easing short and long-term dry conditions in Kenya and southern Ethiopia. Much more rain is needed to end the severe long-term rainfall deficits over pastoral areas of Kenya, but the rainy season appears to be starting on schedule. Showers also helped to ease short-term dryness in Tanzania, Rwanda, and Burundi. In West Africa, unusually warm and dry weather persisted over Togo, Benin, and Nigeria, although scattered thunderstorms brought some relief to coastal Nigeria. Abnormally warm, dry weather continued over Morocco, Algeria, and Tunisia, as rainfall remained scanty. Amounts have totaled under 25% of normal in the past 4 weeks in southern Morocco, northeastern Algeria, and northern Tunisia. Beginning in early April we will reinitiate coverage of the Intertropical Convergence Zone as it migrates northward and compare it against its climatological position. This information will be posted within our USAID/FEWS web site.
April 4, 2001

A path of storminess continues on a path at about 11S. While the areas of depression have not been forecast to magnify into an actual cyclone they constitute a considerable threat of significant rainfall to the areas of Madagascar and Mozambique. We will maintain watch on these systems as they progress, providing bulletins as necessary. Rains further diminished across flood-affected areas of southeastern Africa, with amounts during the week ending April 2 mostly under 10 mm in Zimbabwe, central Mozambique, southern Malawi, and southern Zambia. Heavy rains eased long-term and short-term dryness in southern Ethiopia and central and western Kenya, as isolated amounts exceeded 75 mm in the core of the drought area in northern Kenya. In contrast, much of Rwanda and Burundi may have missed the recent heavy showers affecting other parts of the region, according to satellite estimates, with amounts under 25 mm in parts of both countries. The rainy season appears to have begun poorly in Rwanda and Burundi, particularly in Burundi. In West Africa, showers increased over Ghana, Togo, Benin and Nigeria, as amounts exceeded 75 mm locally during the past week, but more rain is needed to overcome the deficits built up during March. Abnormally warm, dry weather continued over Morocco, Algeria, and Tunisia, as rainfall was light to nonexistent. No measurable rain fell during the entire month of March at a number of locations in Algeria's crop region. Amounts from all three countries generally totaled 0 to 25% of normal in March. Heat aggravated dryness, as monthly temperatures averaged 3 to 5 degrees C above normal.
April 11, 2001

We continue to maintain watch on the evolution of the Pacific La Nina situation. Currently, relatively warm surface water has been observed over the eastern tropical Pacific ocean. However, the subsurface warm water remains to the west and has shown little indication that it will soon migrate to the east. Thus, we linger within a transition period with conversion to an El Nino state perhaps some months away. Abnormally dry weather spread across northern and eastern Ethiopia and much of Somalia during the past week. The first season (belg) rains have been erratic over Ethiopia this season, with below-normal rains over eastern agricultural areas and normal to above normal in the west. Because of little rain in the past 2 weeks, dryness has increased in the east and is developing in the north. In Somalia, the main rainy season has been slow to start, with showers limited to the far south. The median start of the rainy season is the first week of April. In contrast, the rainy season is in full swing over Kenya, contributing to long-term drought relief in the pastoral areas. Satellite-estimated rainfall totals improved over Rwanda and Burundi, but the season has been abnormally dry over northeastern and central Tanzania. Abnormally wet conditions have developed across large areas of central and southwestern Africa, as heavy showers dropped over 75 mm of rain locally in Angola, Namibia, Congo, and DRC during the week ending April 9, according to satellite estimates. Estimated totals exceeded 150 mm in parts of western Angola and even in isolated parts of northern Namibia. Rainfall continued to diminish across the areas of southeastern Africa affected by flooding, as amounts in Zambia, Malawi, Zimbabwe, and Mozambique generally totaled 10 mm or less. Scattered thunderstorms continued along the coast of the Gulf of Guinea, but abnormal dryness persisted over interior parts of Togo and Benin and as well as northern Ghana and western Nigeria. In North Africa, drought worsened across Morocco, Algeria, and central Tunisia, as warm and dry weather continued. Significant rains were limited to northern Tunisia.
April 19, 2001

Another week of little or no precipitation worsened drought affected areas of Morocco, northern Algeria, and central Tunisia, with the Climate Prediction Center rainfall estimates recording precipitation only in extreme northeast Algeria and northern Tunisia. Weekly totals were generally less than 25 mm in the aforementioned areas. Monsoonal rains continued in the Gulf of Guinea with light rains advancing into the interior parts of the Gulf of Guinea. Parts of Cote D'Ivoire received an excess of 125 mm for the period from April 10-16. On April 15, after an intense rain-producing storm, as much as 75 mm rainfall was recorded in west-central areas of the country. While southern Nigeria continued to receive rainfall amounts exceeding 100 mm in some areas, most of Togo and Benin, as well as northwestern Nigeria remained quite dry with barely 10 mm reported for the week. Heavy rains continued in central South Africa, Angola, DRC, and Cameroon with local rainfall estimates exceeding 150 mm. However precipitation lessened somewhat in regions of Central Africa Republic and Congo. Flood-affected regions of Mozambique, Zimbabwe, Zambia, and Malawi continued to recover as generally little precipitation fell in the areas. This coincides well with the ITCZ's climatological jump north in early April and the ending of the monsoon in southeastern Africa. Much of eastern Africa remains dry through this period, although some areas have seen recent relief. Southern Somalia and southwestern Ethiopia received as much as 100 mm the past week, bringing a little relief to the areas, but most of their northern regions saw less than 10 mm. The northern half of Tanzania, as well as Uganda continued to receive good rainfall amounts exceeding 50 mm in most areas, but south-central Tanzania, Burundi, and Rwanda picked up generally less than 30 mm.
April 25, 2001

Since early February 2001, sea surface temperature's (SST) have become anomalously warm in many sections of the eastern tropical Pacific, while remaining below normal in the central equatorial Pacific. Positive SST anomalies were also observed in the eastern equatorial Pacific during March-April 1999 and 2000. In both of those years the anomalous warming of the eastern equatorial Pacific SSTs lasted until late April or early May and then rapidly disappeared as cross-equatorial flow from the Southern Hemisphere into the Northern Hemisphere became established and seasonal rainfall began to increase over Central America, southern Mexico and the southeastern tropical North Pacific. Over the past two years there has been a gradual expansion of the area of positive equatorial subsurface temperature anomalies into the central Pacific. This evolution is consistent with a slow decay of the subsurface thermal structure that characterizes the mature phase of cold episodes. Thus, it is likely that cold episode conditions will gradually weaken over the next several months, with near-normal conditions likely during the summer of 2001. Thereafter, the models indicate near-normal or slightly warmer-than-normal conditions during the second half of 2001. This has implications for the June-August climate in western Africa and we will continue to monitor the situation. Heavy showers spread across much of East Africa, easing long-term drought in Kenya and parts of Ethiopia. However, rainfall amounts remained below normal in northern Ethiopia from Addis northward, an area that has seen little rain since late March, according to satellite estimates and scattered observations. Satellite imagery for April 22-23 suggests a sharp increase in shower activity over eastern Ethiopia, including the Somali region, an area that has been abnormally dry. A few showers even penetrated northern Somalia (Somaliland). Heavy rains across southern Somalia may have been locally excessive, with weekly estimated amounts over 100 mm. In contrast, unfavorably drier weather returned to the Burundi-Rwanda area, with weekly amounts well under 25 mm. Showers continued to ease dryness over the interior of the Gulf of Guinea countries, although an area of dryness persisted from northeastern Ghana through northern Togo and northern Benin into northwestern Nigeria. Light to moderate rains during April 20-22 brought slight drought relief to North Africa, especially coastal areas of Algeria and Tunisia. In southern Africa, unseasonably heavy rains fell in much of South Africa, southwestern Botswana, central and southern Namibia and pockets along the eastern coast of Madagascar. Amounts continued to diminish in the flood-affected areas of southeastern Africa, as little or no rain fell in central Mozambique, Malawi, southern and western Zambia and much of Zimbabwe. The drier pattern coincides well with the slow movement of the ITCZ to the north of southern Africa. Note from the CPC Website that the ITCZ appears to be slightly north of the climatological position in the west and south in the east.
May 2, 2001

Following a 3-week dry spell, seasonal rains resumed in northern Ethiopia, where rainfall exceeded 25 mm locally. Light rain continued to relieve dryness in eastern Ethiopia, while satellite estimated rainfall diminished in southern Somalia, where amounts had been locally heavy during the previous week. Seasonal rains continued to offer spotty long-term drought relief in northern Kenya and southern Ethiopia. Satellite data indicated that unseasonably dry weather covered Rwanda, Burundi and northern Tanzania for the second week. Unseasonably wet weather covered large areas of southwestern and west-central Africa from the Congo to South Africa, with especially heavy rains extending from Namibia southward to central South Africa on April 30- May 1. Rainfall amounts exceeding 40 mm in 24 hours over Namibia and near the extreme western portions of South Africa's summer crop areas would be unusual at the height of the rainy season, but are expecially unusual in late April-early May. Near-record rainfall amounts for this time of year have covered Namibia and western and central parts of Botswana and South Africa during the past 4 weeks. In West Africa, locally moderate to heavy showers eased dryness during the past week in northern areas of Ghana, Togo, Benin and Nigeria, but cumulative rainfall totals for the past 4 weeks continue to be less than one-half normal over parts of this area and over southern Burkina Faso. In North Africa, rains brought some drought relief to the region, with up to 25 mm falling in the past week over Algeria. Rainfall was lighter in Tunisia and Morocco, with negligible rain falling over Morocco's southern crop areas, where the drought is most intense.
May 9, 2001

The slow evolution of the La Nina event continues and it is likely that near-normal conditions will exist during the summer of 2001. Thereafter, the models indicate near-normal or slightly warmer-than-normal conditions during the second half of 2001. This has implications for the June-August climate in western Africa and we will continue to monitor the situation. Locally heavy showers further eased dryness in northern Ethiopia and northern Somalia during the first week in May, but drier weather spread across southeastern Ethiopia and much of Kenya, and little rain fell over central and eastern Tanzania. Parts of northern, eastern, and southern Kenya have recorded negligible rain for 3 weeks. Four-week cumulative rainfall has been near or under 50% of normal in these areas, and similar dryness has affected parts of eastern Ethiopia and northern and central Tanzania. Rainfall increased in the Rwanda, Burundi, northwestern Tanzania region, easing dry conditions. In southwestern Africa, rainfall diminished in areas recently hit by excessive rains, although unseasonably heavy rains did hit parts of eastern Namibia, southern Botswana, and western South Africa once again in the past week. To the north, the rainy season has been slow to start in southern Chad, northern Central African Republic, and south-central Sudan. Rainfall has been negligible in this region during the past 3 weeks, and high temperatures have further increased dry conditions. Additional light to moderate rains fell over North Africa from northern Morocco to Tunisia, but the moisture comes too late in the season to have a significant impact on the drought. The rains missed most of southern Morocco, where the drought is most severe.
May 16, 2001

As indicated in previous weeks, it is likely that near-normal sea surface temperature conditions will exist in the Pacific during the summer of 2001. Thereafter, the models indicate near-normal or slightly warmer-than-normal conditions during the second half of 2001. We are currently computing the July-August-September forecast for the Sahel and the forecast will be available next week. We note also that the international climate forum will be held next week with the resultant consensus forecast. Dry conditions intensified during the past week over much of Kenya, southern Ethiopia, interior southwestern Somalia, northern Tanzania, Rwanda and Burundi, as this area recorded little or no rainfall. For eastern Kenya and adjacent parts of Ethiopia and southwestern Somalia, this was the second week of dry weather. Elsewhere, seasonably dry weather prevailed across southwestern Africa from Angola to South Africa following persistent wetness since late March. To the north, increased showers (1-25 mm, locally heavier) dampened dry soils from southern Chad through northern Central African Republic to south-central Sudan. This area had seen virtually no rain in the prior 2 weeks. In West Africa, the rainy season continued weak in southwestern Burkina Faso, with rainfall amounts mostly under 25 mm. Over North Africa, moderate to locally heavy rains further eased dryness in northern Tunisia, but lighter amounts fell in Algeria, and little or no rain fell in Morocco.
May 23, 2001

Guidance for the Sahel Rainfall in Jul-Aug-Sep 2001 At One Month Lead The Sahel, defined here as the region between 10-25 N and 18 W-45 E, receives the bulk of its annual mean rainfall during the northern hemisphere summer when the ITCZ reaches its northernmost position. For our forecast method, quasi-global SSTs between 40 S and 60 N at a resolution of 10 by 10 lat-lon are used to predict the Sahel rainfall. The diagnostic data produced by the statistical analysis indicate that the current weak cold episode of ENSO does not have much impact on the forecast for Jul-Aug-Sep Sahel rainfall at one month lead. However, cold SSTs over the equatorial central Pacific tend to be associated with above normal rainfall over the Sahel. NCEP statistical and coupled model forecasts, as well as other available coupled model and statistical model predictions, indicate a gradual weakening of cold episode conditions during the next few months. Another factor modulating rainfall over the Sahel is Atlantic SSTs. Over the past year, near-to-above-normal SSTs prevailed across much of the Atlantic. Consistent with the weak global SST anomalies, the current forecast does not have much skill in the prediction of Jul-Sep 2001 Sahel rainfall and calls for climatology in many parts of the region. However, slightly higher than climatological probabilities for above normal rainfall are expected over western Senegal, southwestern Mauritania, central Mali, and eastern Chad, while slightly higher than climatological probabilities for below normal rainfall are expected over parts of central Sahel. During the past week, little or no rain fell over eastern and southern Ethiopia, as well as much of Somalia and Kenya, increasing the risk that the rainy season may be coming to an early end. This would especially be a concern for eastern Ethiopia, where the rainy season began several weeks late. The season may also be ending early in Rwanda, Burundi, and northwestern Tanzania, as rainfall amounts were light in this region. Increased rainfall improved dry conditions in south-central Sudan and northern Central African Republic, but rainfall deficits persisted. Weekly amounts of 1 to 25 mm did little to improve rainfall deficits in southeastern Chad, but greater amounts fell in the southwest. Moderate to heavy showers eased dryness in western Burkina Faso, as lighter rains fell from southern Mali into Guinea. The rainy season has been somewhat slow to start in this region. Rainfall has also diminished over interior portions of Cote d'Ivoire, Ghana, Togo, and Benin, with much of this area recording 4-week accumulations under 50% of normal. In contrast, locally heavy rains left as much as 200 mm along the coast of Cote d'Ivoire. This pattern is in agreement with the observed location of the ITCZ being a bit south of the normal position in the east and near normal in the west.
May 30, 2001

During the past week, little precipitation fell once again through much of eastern and southern Ethiopia, while western parts of the country received amounts exceeding 150 mm. Rainfall was sparse throughout most of Somalia, as only northern areas accumulated more than 20 mm. Dry conditions continued in most of Kenya and Tanzania, and light showers continued in eastern coastal areas of Madagascar. It appears that the rains are diminishing on schedule in these areas of eastern Africa. Widespread rains fell throughout southern Sudan, with common values exceeding 30 mm, and amounts estimated up to 100 mm. These rains extended into all of eastern CAR, but did not continue through southern Chad as generally less than 15 mm fell. The ITCZ in this area does continue to be more southward than the climatological mean, but movement has generally been northward the past few weeks as expected. See http://www.cpc.ncep.noaa.gov/products/african_desk/ITCZ/ITCZ.html for further information. Healthy rainfall amounts fell throughout interior portions of sub-sahelean Africa, with amounts exceeding 75 mm somewhat common. The region around Sierra Leone has been slightly dry the past month, and precipitation amounts less than 30 mm for the week ending May 28 are representative of the season so far.
June 6, 2001

For the last assessment we discussed the outlook for West Africa region based on the CPC Africa Desk long-lead forecast. Included with this assessment is a sahel.pdf file of the consensus forecast developed at the West Africa Climate Forum. As indicated from our previous discussion, the area forecast is generally for climatology reflecting the transition state of the sea surface temperatures. The exception is in Zone III from Liberia to southwest Nigeria where an above normal precipitation is forecast. The rainy season has ended somewhat early across the African Horn. Little or no rain fell during the past week in the Somali region of southeastern Ethiopia as well as most of Somalia and Kenya. Only western and coastal areas of Kenya picked up significant rains. Preliminary estimated rainfall for the season from February through May indicate cumulative rainfall may have been well under 50% of normal in southeastern Ethiopia, with some locations under 25% of normal. Cumulative rainfall was generally 50 to 80% of normal across Somalia, Kenya, Tanzania, Rwanda and Burundi. In the Sahel, scattered thunderstorms fell over southern Chad, but conditions appear to remain drier than normal, and the dryness appears to extend into extreme northern Cameroon and parts of northeastern Nigeria, although showers brought locally heavy rains to northern Nigeria. Scattered thunderstorms improved moisture conditions in Burkina Faso, southern Mali and Guinea. The rains have been slow to advance northward into Guinea-Bissau and southern Senegal, but this is too early in the season to be a problem.
June 13, 2001

As depicted in the Climate Prediction Center website at www.cpc.ncep.noaa.gov the Intertropical Convergence Zone in the area of 10-20E remains several degrees latitude south of its climatological position impacting the timing of the seasonal rains in the area. In East Africa, dry weather prevailed from Somalia and eastern Ethiopia southward through eastern Kenya into Tanzania. There is little prospect for significant dryness relief until the second rainy season begins in October. To the west, satellite rainfall estimates as well as vegetation indices continued to point to a slow start to the rainy season in southeastern Chad, extreme northern CAR, and adjacent portions of Sudan. The heaviest rains of the season, with weekly totals mostly over 40 mm, relieved dryness in the western half of southern Chad. Rainfall remained light in southern Niger and adjacent parts of northeastern Nigeria, with weekly amounts mostly under 5 mm. It is, however, still early in the season, and cumulative rainfall for the rainy season could easily be normal if the rains start soon. Some pockets of below-normal rainfall persisted in Burkina Faso, but rainfall has been ample in the southeast. Locally excessive rainfall continued in central and southern Nigeria, with satellite estimates exceeding 75 mm on June 10.
June 20, 2001

The seasonal rains advanced northward into Niger during the past week, improving moisture conditions in northern Nigeria and southern Niger. In contrast, satellite-estimated rainfall diminished in parts of southern Chad and remained light in adjacent west-central Sudan, resulting in continued below-normal moisture conditions, especially from southeastern Chad into Sudan. Locally excessive rains exceeding 100 mm fell in southern Sudan and western Ethiopia. Heavy showers continued in eastern Burkina Faso, but some dry pockets persisted in other areas, especially near the border with Ghana, according to satellite estimates and ground stations.
June 27, 2001

While the position of the ITCZ has been south of its normal latitude over the previous weeks, during the second dekad of June, the ITCZ advanced north in the mid-section of the continent to its more normal position. The latest maps of the ITCZ location can be viewed on the Climate Prediction Center Homepage at: http://www.cpc.ncep.noaa.gov/products/african_desk/ITCZ/ITCZ.html For the period from June 19-25, 2001, rainfall was generally seasonal over most of the African continent with the exception of unusually heavy rains in parts of southern Africa. Parts of eastern Botswana and central South Africa received up to 35 mm total precipitation, while widespread amounts greater than 10 mm were estimated. Tropical Cyclone 21s formed on June 21 in the southern Mozambique Channel with maximum sustained winds of 45 kts, but weakened by the 23rd without making landfall. In eastern Africa, heavy rains once again fell in coastal areas of Kenya and northern Tanzania, with amounts exceeding 100 mm locally. Little or no rain fell in Somalia and eastern Ethiopia, but western Ethiopia accumulated scattered amounts of 75 mm, with a large region of 30 mm or greater totals. Seasonally heavy rains totaling greater than 100-200 mm fell again in coastal Cameroon and eastern Nigeria, and local totals exceeding 100 mm were estimated in areas of Ghana, Togo, and northern Nigeria. Generally, the monsoonal rainfall pattern coincides well with the latest plotted ITCZ position.
July 4, 2001

Current sea surface temperature data indicate that it is likely that near-normal sea surface temperature conditions will continue to exist in the Pacific during the summer of 2001. Thereafter, the models indicate near-normal or slightly warmer-than-normal conditions during the second half of 2001. The seasonal rains continue to advance northward on schedule over most of the Sahel, although rains remained slow to move into central Senegal. Generally, both the Sahel and Gulf countries recorded moderate showers, while light to moderate rain fell over central and eastern Africa. Unseasonable rains fell in South Africa.
July 11, 2001

The seasonal rains continued favorable across most of the Sahel, although rainfall remained somewhat below normal in parts of Senegal and Gambia. Amounts tapered off significantly over the Gulf of Guinea countries, as the mid-season dry period appeared to take hold. Locally excessive rains exceeding 75 mm fell in western Mali, northeastern Burkina Faso, central and northern Cameroon, and southern Chad. Beneficially drier weather prevailed in areas to the south earlier hit by heavy rains, including Ghana, Nigeria, and southwest Cameroon. In Sudan, the seasonal rains have been slow to become established in northern agricultural areas in the central and western parts of the country.
July 18, 2001

During July 1-10, 2001, the West African portion of the ITCZ remained stationary at 17.4 degrees N, which is close to the long-term mean of 17.5 N. Overall progress so far this season has been typical despite the failure of the ITCZ to advance northward during this period. In contrast, the ITCZ remained south of normal across eastern Africa (20-35 degrees E), its mean position of 14.2 N a full degree south of its long-term mean position. The convergence zone has been consistently south of normal during this season. The ITCZ was near its normal latitude from Mauritania east through Niger, but south of normal over Chad and Sudan. The result has been a tendency for above-normal temperatures, below normal humidity, and below-normal rainfall in the northern crop areas of Chad and Sudan. Within this vein, the seasonal rains continued mostly favorable across the Sahel, although there were some localities with too little rain and some with too much. Weekly rainfall totals of 75 mm and higher in western Senegal, northwest Burkina Faso, and southwestern Niger were locally excessive, while below-normal rains persisted in Senegal's eastern groundnut basin (weekly rainfall under 10 mm) and in the Lake Chad area (under 15 mm). The latter area included west-central Chad, extreme northern Cameroon, and extreme northeastern Nigeria. A westward-tracking thunderstorm complex improved soil moisture on June 16-17 in Niger's central and eastern crop areas. Locally heavy rains reaching 100 mm threatened flooding in central and southeastern Nigeria. Farther west, the midsummer dry period remained intact along the Gulf of Guinea coast, despite spotty heavy rains in southern parts of Togo and Benin. In Sudan, the seasonal rains progressed northward, bringing beneficial moisture to Sahelian crop zones. However, estimated rainfall totals (2-20 mm) remained below normal in west-central Sudan, particularly in Darfur province. Rains may have been locally excessive (exceeding 100 mm) from western Eritrea southward into northwestern Ethiopia and westward into adjacent areas of Sudan, but the moisture may have benefitted parts of Eritrea (Anseba, for example) that had earlier been reported as too dry.
July 25, 2001

For the period July 11-20, the ITCZ advanced about 0.8 degrees north of its position during the previous period. There was still a southward bias from western Chad through eastern Sudan, where the convergence zone was located around 15.3 degrees north, compared to a twelve year mean position of 16.0 degrees north. Though a southward discrepancy exists, it is to a much lesser extent than earlier in the season, when monsoonal rains were much weaker in the region. As is normal for the period, the peak northward position of the ITCZ is occurring around 7.5 degrees west longitude. Partially due to this northward position, seasonal rains have begun to diminish along coastal areas of the Gulf of Guinea. The northward shift of the ITCZ brought important rainfall to northern Senegal, central Mali, central Niger, central Chad, central Sudan and northern Ethiopia. During the past week, beneficial rains fell in areas that had been trending dry, including the Lake Chad area, east-central Chad and west-central Sudan, and parts of Senegal's groundnut basin. The mid-season dry period remained entrenched over Liberia, southern and central Cote d'Ivoire and southern Ghana, while slight rains persisted over southern Togo, Benin and southwestern Nigeria. Unseasonably heavy rain fell over Uganda and surrounding regions and also over the southwestern coast of South Africa.
August 1, 2001

One of the elements we continue to monitor is the sea surface temperature in the Pacific Ocean. Attached (fcstsst.gif) for your information is the latest sea surface temperature forecast, by season, produced by the NCEP, Climate Modeling Branch. We see that the lingering cold surface water in the eastern Pacific is forecast to dissipate by late 2001 and be replaced by relatively warm water by early 2002. We will continue to monitor the timing and magnitude of the warming as it represents possible impacts on the precipitation and temperature over Africa. Rainfall remained generally favorable in the Sahel countries. Weekly rainfall totaled 25 to 50 mm from eastern Senegal to Chad, with locally excessive amounts of 75 mm or more in parts of Mali and southern Chad. Amounts were lighter in central Sudan, west-central Chad, southeastern Niger, Gambia and Senegal's groundnut basin, but these areas saw beneficial rains in the prior week. To the south, rainfall totaled only 0 to 10 mm in Liberia, southern Cote d'Ivoire, and southern Ghana. Parts of southern Cote d'Ivoire and southern Liberia have seen little rain in the past 3 weeks. In contrast, rains exceeded 75 mm for the second week in northeastern Nigeria and extreme northern Cameroon. Satellite-estimated amounts reached 200 mm locally along Nigeria's southeastern border with Cameroon.
August 8, 2001

Continuing our discussion of the sea surface temperatures from last week, over the past two years there has been a gradual expansion of the area of positive equatorial subsurface temperature anomalies into the central Pacific and a gradual decrease in the strength and areal extent of the negative subsurface temperature anomalies in the eastern Pacific. This evolution is consistent with the decay of the subsurface thermal structure that characterizes the mature phase of cold episodes and the development of conditions usually found just prior to warm episodes. Accompanying this evolution has been a gradual transition from negative to positive SST anomalies between 160°E and 130°W. Positive SST anomalies are likely to continue in the equatorial Pacific during the remainder of 2001 and into the first half of 2002. This assessment is consistent with most coupled model and statistical model predictions that indicate warmer than normal oceanic conditions through early 2002. The impacts that this warming will have on global temperature and precipitation patterns depend to a large degree on its intensity. At the moment, there is considerable spread in the predicted SST anomalies, with most predictions indicating a weak or moderate warm episode (El Nino) by the end of 2001 and the beginning of 2002 Weekly updates for SST, 850-hPa wind, OLR and the equatorial subsurface temperature structure are available on the Climate Prediction Center homepage at: http://www.cpc.ncep.noaa.gov (Weekly Update). Forecasts for the evolution of El Nino/La Nina are updated monthly in CPC's Climate Diagnostics Bulletin Forecast Forum. This ENSO Diagnostic Discussion, which replaces the ENSO Advisories, will appear regularly around the 10th of each month on the CPC web site. Rainfall remained mostly favorable across the Sahel, with weekly amounts mainly in the 25 to 75 mm range. Less rain fell in the west. Although increased rains benefitted Gambia and Senegal's southern groundnut basin, amounts were below normal (1-10 mm) in eastern and northern Senegal, including the northern groundnut basin. Rainfall has been consistently below normal in this area during the current growing season. To the south, dryness persisted in Liberia and central and southern parts of Cote d'Ivoire and Ghana, with little or no rainfall. Amounts were also low in southern parts of Benin and Togo. A break in the rains is expected during this time of the year in the Gulf of Guinea countries, but rainfall amounts have been less than usual, especially from southern Liberia eastward to southwestern Ghana. Locally heavy rains exceeding 75 mm fell in east-central Chad and adjacent Sudan, as well as western Cameroon and southwestern Sudan and northwest Ethiopia. In contrast, rainfall amounts appeared to be light (1-10 mm) in south-central Sudan.
August 15, 2001

During August 1-10, the African ITCZ resumed this years general pattern, with the western region located north of the climatological mean, and the eastern region located south of the mean. The western region of the ITCZ (10 degrees west to 10 degrees east) was located on average at 20 degrees north, compared to the long-term mean position of 19.1 degrees . The ten day movement from last period of almost one degree north continued to influence diminishing rains along the Ivory Coast and increasing rainfall in Sahelian western Africa. The eastern region of the ITCZ (from 20-35 degrees east) did not see this trend in average movement, but actually moved about a half degree south of its position last period. Although this southward bias did not appear to affect rainfall in the region, this may be a hint that the ITCZ has reached its maximum northward position earlier than the 1988-2000 climatological figures indicate. Rainfall has increased, generally, over much of the Sahel countries compared to the previous 10 day period. Pockets of short-term dryness over Burkina Faso and central Senegal received moderate showers during the last days of this period. Examination of the meteorological circulation shows a trough along Morocco maintaining the western branch of the ITCZ to a higher position (23 degrees north). This extends precipitation over northern Mauritania and Mali. Mid-season dryness persisted over southern Liberia, southern and central Cote d'Ivoire, most of Ghana, southern Togo and Benin, southwestern Nigeria and southern Cameroon.
August 22, 2001

CCA Guidance for Sahel Rainfall in Aug-Oct 2001 at One Month Lead With the sea surface temperature anomalies across the central equatorial Pacific increasing over the past several months the CCA forecast for the Sahel has been updated for the period August-October 2001. The Sahel, defined here as the region between 10-25N and 18W-45E, receives the bulk of its annual mean rainfall during the northern hemisphere summer when the ITCZ reaches its northernmost position. The prediction for Aug-Oct 2001 Sahel rainfall at one month lead calls for slightly higher than climatological probabilities for below normal rainfall across much of western and central Sahel from Senegal to western Niger. Slightly higher than climatological probabilities for above normal rainfall are predicted over parts of northern and central Ethiopia. Climatology is suggested elsewhere. Tropical waves continued to bring ample rainfall from western Ethiopia to Mali, but they tended to weaken or dive southward approaching Senegal. As a result, unusually warm, dry weather prevailed across Mauritania and northern and central Senegal during the past week. Senegal's northern and western groundnut basin measured under 10 mm of rain, with some locations in both Senegal and Mauritania reporting no rainfall from August 8 to 20. As this is near the critical stage of the crop season, rainfall will be very important in coming days and we will continue to monitor the situation. Rainfall amounts were higher (25-50 mm), although still below normal, from western Gambia and southern Senegal southward through Sierra Leone. Locally excessive rains exceeding 100 mm fell in Burkina Faso. Dry weather again prevailed from Liberia eastward through central and southern parts of Cote d'Ivoire and Ghana and into southern parts of Togo, Benin, and Nigeria. The mid-season dry period has been slightly drier than normal this summer in the Gulf of Guinea countries.
August 29, 2001

During August 11-20, 2001, the West African portion of the ITCZ retreated a small distance southward to 19.6 degrees N, which was north of the long-term mean of 19.3 N and 0.4 degrees south of its previous position (August 1-10, 2001). Overall progress so far this season has been fairly typical, except for a spike northward during August 1-10. The western ITCZ would have been near the 20th parallel again this period if not for strong northerly winds in the west during August 18-20 driving the humid air southward across Mauritania. In the east, the ITCZ jumped to its most northward position of the season, averaging 17.8 N from 20 to 35 degrees E longitude. This was 0.5 degrees north of the 1988-2000 mean and a significant advance of 1.4 degrees from the previous position. Tropical waves again brought abundant rainfall to the Sahel countries and eastward through Sudan. Weekly (August 21-27) rainfall totals ranging from 10 to 25 mm improved moisture conditions in northern Senegal, although rainfall deficits remained. Another 20 to 60 mm fell in Senegal's groundnut basin on August 28, but less fell to the north, where 4-week rainfall accumulations remained well under 50% of normal. Totals of 10 to 50 mm also boosted conditions in Mauritania. Excessive rains, with amounts exceeding 75 mm, fell in southern Burkina Faso, northern parts of Ghana, Togo, Benin, and Nigeria, southern Chad, parts of the Central African Republic (CAR), southwestern and eastern Sudan, and northwestern Ethiopia. Weekly totals exceeded 100 mm in parts of southern Chad and western CAR. Two of the last 3 weeks have been abnormally wet in southern Chad. In east-central Sudan's Nile basin, this was the second week that saw locally heavy rains, resulting in increased flood threat. Although heavy showers fell in northwest Ethiopia, estimated amounts were light in south-central areas, totaling under 10 mm south of Addis. Long-term drought persisted over southeastern Ethiopia, the pastoral areas of Kenya, and much of Somalia. Rainfall increased over the southern and central Gulf of Guinea countries, although little rain fell along the coast from southern Liberia to southern Nigeria. Heavy rains eased dryness in central Cote d'Ivoire on the 28th.
September 6, 2001

With the West African portion of the ITCZ at about its most northernmost position, the easterly waves coming off the coast pose the potential for hurricane development in the Atlantic Ocean. The Climate Prediction Center forecast for this hurricane season is: Expected Level of Overall Activity - Normal Our forecast is for a 50% chance of normal levels of activity during the 2001 Atlantic hurricane season, a 25% chance of above-normal activity and a 25% chance of below-normal activity. The active tropical waves across the Sahel countries resulted in scattered areas again recording heavy rainfall amounts. Totals exceeded 75 mm for the week ending August 3 in east-central and west-central Chad, southern Nigeria and adjacent southern Cameroon, isolated locations in northern Nigeria, southern and southeastern Burkina Faso, and southern and central Mali. Lighter amounts falling over southern Chad, northern Nigeria and eastern Sudan reduced the flood threat in these countries. The moisture further reduced dryness over Senegal's groundnut basin, although rainfall deficits remained in parts of Senegal, especially in the north. A large complex of thunderstorms crossed Mali and Senegal during August 4-5. In Ethiopia, satellite estimates suggest below-normal rainfall in the west to the south of Lake Tana during the past 4 weeks and over central areas during the past 3 weeks. Heavy rainfall diminished in northwest Ethiopia. Rainfall remained light along the Gulf of Guinea coast from southern Liberia to southwestern Nigeria. Increased rainfall inland suggested the mid-summer dry period will soon end. In southern Africa, abnormally heavy rains extended from the Free State southward through Lesotho to the coast, with the possibility of heavy snow in Lesotho's mountains. A second week of heavy showers hit the Cape Town area, where flooding has been reported.
September 13, 2001

During the period from September 1-10, the African ITCZ maintained similar spatial characteristics from the pervious period, but continued a general southward movement. The average position of the western ITCZ region (from 10 degrees west to 10 degrees east longitude) is just south of its location during the final ten days of August. This position is reflected by the continued lack of rainfall in areas of Liberia and Cote D'Ivoire, with heavier rains extending from Senegal through northern Nigeria. The current eastern ITCZ position, averaged from 20-35 degrees east longitude remains with a southward bias from the climatologically mean position on the order of one degree. The peak northward position did occur in mid-August. This feature is reflected in the cumulative satellite estimated rainfall map for the same period, with a lack of precipitation in areas of central Sudan. Overall, the average position of the African ITCZ is similar to the 1988-2000 mean, but a discrepancy does exist in eastern regions. Associated with the ITCZ, tropical waves continued to track westward across the Sahel countries, bringing additional heavy rains to scattered areas. Reflecting the usual seasonal shift in the weather pattern, the rainfall band retreated southward across the central and eastern Sahel region, and amounts were not quite as heavy as in preceding weeks. Totals of 50 to 75 mm during September 4-10 threatened additional or continued flooding in eastern Sudan, northwestern Ethiopia, southern Chad, northern Nigeria, southwestern Cameroon, southern Mali, and central Senegal. Excessive rains exceeding 75 mm also hit Uganda to the north of Lake Victoria. Increased rains fell over southwestern Ethiopia, which had been abnormally dry in early to mid-August, according to satellite estimates, but rainfall remained light in central Ethiopia, continuing a dry trend that began in late July. Estimated amounts also remained light in the eastern Darfur region of west-central Sudan, where satellite vegetation imagery implies below-average conditions and the ITCZ has been persistently south of normal. Beneficial drier weather prevailed across South Africa.
September 20, 2001

Although most oceanic and atmospheric indices reflect ENSO-neutral conditions, there are indications that a warm episode will develop during the remainder of 2001. Over the past two years there has been a gradual eastward shift of the area of positive equatorial subsurface temperature anomalies from the western equatorial Pacific into the central equatorial Pacific. This evolution is consistent with the decay of the subsurface thermal structure that characterizes the mature phase of cold episodes and the development of conditions usually found just prior to warm (El Nino) episodes. Accompanying this evolution has been a gradual transition from negative to positive SST anomalies and a gradual return to near normal low-level winds in the central equatorial Pacific. There is no clear consensus amongst the latest statistical and coupled model predictions. However, several of these predictions indicate that positive SST anomalies will continue in the central equatorial Pacific during the remainder of 2001 and into the first half of 2002. The impacts that this warming will have on global temperature and precipitation patterns depend to a large degree on its intensity. At the moment, considering both the SST predictions and the observed oceanic and atmospheric circulation patterns, it seems most likely that the intensity of the warming will be weak or moderate. Weekly updates for SST and other features of the equatorial thermal structure are available on the Climate Prediction Center homepage at: http://www.cpc.ncep.noaa.gov. Unseasonably heavy rains struck Lesotho and southeastern South Africa in the Kwazulu-Natal area on September 11-13, with totals ranging from 75 to 150 mm. This compares with normal weekly totals in the 5 to 10 mm range. Another storm system dropped heavy rains on Northern and Eastern Cape Provinces and western Free State during September 18, with reported 24-hour amounts up to 65 mm. This contrasts sharply with normal weekly totals of 1 to 3 mm. Isolated heavy showers also hit Angola, Namibia, and southern Mozambique during the week. To the north, the seasonal rains continued their typical southward migration, as rainfall tapered off in parts of the Sahel and increased along the Guinea Gulf. Estimated rainfall amounts during the week ending September 17 reached 100 to 200 mm in southeastern Nigeria. Moderate rains of 10 to 50 mm eased dryness in southern parts of Liberia, Cote d'Ivoire, Ghana, Togo, and Benin. Excessive totals of 75 mm or more hit parts of southwestern Sudan and southern Chad, as well as much of the Central African Republic. Rains eased dryness in the southern parts of Sudan's Darfur province, but totals remained light in the northern crop areas of eastern Darfur.
September 27, 2001

During September 11-20, 2001, the West African portion of the ITCZ retreated 1.2 degrees latitude southward to 17.5 degrees N, which is near the long-term mean. Overall progress this season favored ample and timely rainfall for the Sahel countries. In the east, the ITCZ's average position of 15.2 N was near last period's location (15.1 N) and 0.5 degrees south of its 1988-2000 mean. The ITCZ was near its normal latitude over Mauritania and Mali, but south of normal from Niger to western Sudan. Heavy rains diminished in central South Africa after September 19 while favorably dry weather prevailed over previously-wet areas in southeastern South Africa and Cape Town in the west. To the north, locally heavy rains exceeding 75 mm in the past week fell over southern Chad, western Nigeria, and southwestern Cameroon. Rainfall totals exceeded 100 mm in western Kenya near Lake Victoria, but long-term drought continued over northern and eastern Kenya, Somalia, and southeastern Ethiopia.
October 4, 2001

During the period from September 21-30, 2001, the western region of the African ITCZ retreated 0.9 degrees southward from its previous position while the eastern ITCZ region retreated approximately 0.7 degrees southward. For most of the season the western region has been very close to its normal position while the eastern region has been generally located south of normal. The latest dekadal satellite-estimated rainfall map indicates a correspondence between rainfall location and ITCZ position, as rains have increased southward into the coastal Gulf of Guinea and central African locations. Heavy rains (75-150 mm in the past week) persisted in northwest Nigeria and expanded across southeast Nigeria and Cameroon's border area. Locally heavy rains exceeding 75 mm also hit Cote d'Ivoire, Ghana, Togo, and Benin. Conditions likely remain too wet in parts of the southern half of Sudan, with another 25 to 50 mm of rain and locally heavier amounts. Little or no rain fell across the long-term drought areas of southern and southeastern Ethiopia and northern and eastern Kenya, as well as southern Somalia. Scattered showers did fall over central and northern Somalia, likely signaling the start of the minor rainy season there. The minor season rains should start soon elsewhere across the African Horn, as the season typically begins by early October. Satellite imagery shows an increase in mid-level moisture, suggesting rainfall will increase shortly. The season has started late along the southeast coast of Kenya and the northeast coast of Tanzania, where normal weekly rainfall is 15-20 mm and amounts varied from 0 to 4 mm.
October 11, 2001

As there have been several tropical depressions already observed in the South Indian Ocean, we include within this preamble the current sea surface temperature information for this region. Within sst.gif we see that the South Indian Ocean for the period September 30 - October 6 is generally about 0.5-1.5 degrees above the 1961-1990 average with slightly warmer temperatures between Indonesia and Australia. In general, these warmer sea surface temperatures are more conducive to enhanced cyclone activity due to greater availability of tropical energy. These sea surface temperature products are updated weekly by the NCEP/Environmental Modeling Center and are found at the web site: www.emc.ncep.noaa.gov/research/cmb/sst_analysis We will continue to monitor the sea surface temperatures and the cyclone development throughout the season. Satellite estimates indicated heavy rainfall amounts of 75 to 200 mm during the week ending on October 8 in extreme southern Sudan (Eastern Equatoria Province). This is more rain than is normally experienced during the entire month of October. In contrast, dry weather dominated the African Horn, with only widely scattered showers over Somalia, southern Ethiopia, the pastoral areas of Kenya, and most of Tanzania. Rainfall has been abnormally light since September in southeast coastal Kenya and northeast coastal Tanzania. More recently, the onset of the minor season rains has been somewhat late in Somalia, southern Ethiopia, Kenya's pastoral areas, and northern Tanzania. Much of this region is already affected by a long-term drought.
October 18, 2001

Most oceanic and atmospheric indices reflect ENSO-neutral conditions. However, there are indications that a warm episode may develop during the next several months. Since late June 2001 sea surface temperatures (SSTs) have become anomalously warm in the central equatorial Pacific, with anomalies near 1°C in the vicinity of the date line. During the same period, subsurface temperature anomalies have remained positive in the central equatorial Pacific between 170°E and 120°W, indicating a deeper than normal thermocline in that region. This pattern has been observed during the early stages of past warm episodes. In recent months, many tropical Pacific atmospheric and oceanic variables have been modulated by intraseasonal (30-60 day) activity. In the past, such activity has been instrumental in producing low-level wind fluctuations during both the onset and demise phases of warm episodes. Since we are currently in a transition season, special attention will be focused on the evolution of this activity and any effect that it has on surface and subsurface ocean temperatures. There is no clear consensus amongst the latest statistical and coupled model predictions. However, several of these predictions indicate that positive SST anomalies will continue in the central equatorial Pacific during the remainder of 2001 and into the first half of 2002. The impacts that this warming will have on global temperature and precipitation patterns depend to a large degree on its intensity. At the moment, considering both the SST predictions, the time of year and the observed oceanic and atmospheric circulation patterns, it seems most likely that the intensity of any warming will be weak or moderate. In East Africa, the minor season rains continued below normal, with weekly totals during October 9-15 of 0 to 10 mm over extreme southern Ethiopia, southern Somalia, the pastoral areas of Kenya, and northern Tanzania. Four-week rainfall has totaled less than 25% of normal along the coast of Kenya and at scattered locations in the interior. Areas of southern Ethiopia farther north did measure up to 10 mm of rain, easing short-term dryness. Farther west, rainfall amounts diminished from the excessive levels recorded during the previous week in southern Sudan and northern Uganda. In southern Chad, a large thunderstorm complex brought heavy rains on October 16, threatening renewed flooding.
October 25, 2001

During the period from October 11-20, 2001, the African ITCZ continued moving southward at a slightly faster than normal pace. The western region (10° west to 10° east) was located on average 1.1° south from the previous period, and 0.9° south of its climatological normal position southward bias remains for the eastern region of the ITCZ from 20-35° east, a pattern that has virtually existed for this entire season. A look at the 10-day satellite estimated rainfall map shows precipitation prominent throughout the CAR, and some amounts exceeding 50 mm for the period in northern Angola. This pattern coincides well with the southward movement of the ITCZ. Light rains prevailed across much of the Greater Horn of Africa, signaling a slow start of the short rainy season. The exception was central and western Ethiopia, where favorable rains were observed. Consistent with the southward retreat of the ITCZ, heavy downpours soaked central and southeastern Nigeria. Although rains remained steady throughout most of southern Uganda, a lack of precipitation occurred along coastal areas of Kenya and southern Somalia, where five week rainfall totals are less than 20% of normal. As opposed to late September/early October, rainfall was generally light over northern Algeria and Morocco as drier air pushed through the region, while temperatures averaged 2-7 degrees warmer than normal. Lighter rains continued over parts of eastern Guinea and southern Chad, but totals moderated to generally less than 40 mm, as opposed to more excessive amounts that fell in September. Heavy rains soaked areas of coastal Cote d'Ivoire, Ghana, central Gabon, and southern Congo, with totals exceeding 100 mm locally. These rains in the Gabon region helped to ease the dryness that has been affecting the area, but short term dryness still remains further south into northern Angola. In southern Africa, unseasonable moderate rains fell over Zimbabwe. Moderate to heavy rains were also observed over northeastern South Africa. Elsewhere, locally moderate rains were observed over central and western Zambia, northeastern and northwestern Mozambique, northern and southeastern Madagascar.
October 31, 2001

The first named cyclone (Alex/Andre) of this season in the South Indian Ocean has occurred and we note that in early October we included a discussion of the observed sea surface temperature information for this region. For this preamble we update this information and within sst.gif we see that the South Indian Ocean for the period October 21-27 remains about 0.5-1.5 degrees above the 1961-1990 average with slightly warmer temperatures in the vicinity of Indonesia. In general, these warmer sea surface temperatures are more conducive to enhanced cyclone activity due to greater availability of tropical energy. These sea surface temperature products are updated weekly by the NCEP/Environmental Modeling Center and are found at the web site: http://www.emc.ncep.noaa.gov/research/cmb/sst_analysis. In East Africa, showers (10-75 mm) covered southern and southeastern areas of Ethiopia as well as much of Somalia during the past week, easing short and long-term dryness. The minor rainy season appears to be established over both countries following a somewhat slow start. However, abnormally dry conditions continued over southern Somalia, the pastoral areas of Kenya, and northern and eastern Tanzania, as rainfall totals for the week ending October 30 were negligible. Four-week rainfall has totaled under 25% of normal in central and eastern Kenya, and similar deficits are likely in adjacent southern Somalia and across northern and eastern Tanzania. The recent dryness has aggravated long-term drought over Kenya and southern Somalia. Farther south, heavy rains hit central South Africa, with weekly totals of 75 to 100 mm in the southern part of the maize triangle and up to 200 mm near the coast south of Lesotho.
November 7, 2001

During October 21-31, 2001, the ITCZ continued its rapid retreat southward. The West African portion of the ITCZ (10 degrees W to 10 degrees E) dropped 2.1 degrees latitude south to 11.4 degrees N, which was 1.3 degrees south of the long-term mean. This was the farthest south for October 21-31 since 1989 (11.2 N). In the east (20 to 35 degrees E), the ITCZ's average position of 10.3 N was 1.2 degrees south of last period's location and 1.1 degrees south of its 1988-2000 mean. The ITCZ was located well south of normal over much of its length, with only the far western end over Senegal and the far eastern end over Sudan near the long-term mean location. Consistent with this pattern, plentiful rains fell over western Ethiopia and extreme eastern Sudan, but dry conditions held sway across the rest of the region south to about the 6th parallel from around 25 E to 10 W. This is the last ITCZ update for the year. Resumption of ITCZ monitoring is planned to resume next April. The first named cyclone (Alex/Andre) of this season in the South Indian Ocean dissipated over the mid-Indian Ocean and ceased to be of cyclone strength. The remnants have continued to move westward. It appears the storm system will move just north of Madagascar and will not pose a significant threat to the continent. In East Africa, heavy showers ended dryness across parts of Kenya, with localized totals for the week ending on November 5 reaching 200 mm in southeastern interior areas. Nevertheless, long-term drought persisted across northern Kenya, and pockets of short-term dryness also continued, as weekly totals stayed under 10 mm in some locations. Abnormal dryness also continued over the southern coast of Kenya and across much of northeastern Tanzania. Many stations in the latter area have reported 4-week rainfall totals under 25% of normal. To the north, abnormally wet conditions persisted from Uganda northward to southern Sudan, with estimated amounts exceeding 50 mm in a number of areas, and totals locally reaching over 100 mm in southern Sudan's western Equatoria province. To the south, the summer rains have been slow to start over Mozambique, northern and eastern Zimbabwe, and southern Malawi. Rainfall has been negligible in recent weeks over much of this region.
November 14, 2001

Guidance for Southern Africa Rainfall in Dec-Mar 2001-2002 at One Month Lead Southern Africa is defined here as the region between 10°-35°S; 10-50°E. The prediction for Dec-Jan-Feb 2001-2002 southern Africa rainfall at one month lead (Wassila.gif) is weak and calls for climatology across much of southern Africa. Slightly higher than climatological probabilities for above normal rainfall are predicted for northeastern southern Africa, including northern Mozambique, Malawi, and southern Tanzania. In this forecast, quasi-global SSTs between 40°S and 60°N at a resolution of 10° by 10° lat-lon are used to predict southern Africa rainfall. The predictions are expressed in terms of departures from climatological probabilities for the two extreme categories above and below-normal rainfall. The climatological probability of each of these categories is 0.33. The probability for the normal category remains fixed at 0.33 because the statistical method has virtually no skill in predicting this category. When skill is low, climatology is suggested. Thus, no forecast is made. The diagnostic data indicate that Dec-Feb Southern African rainfall has a modest predictability at 1 month lead. Generous rains spelled some additional relief for eastern and coastal areas of Kenya and southern Somalia. Rainfall intensified over central and northern DRC. Wet conditions persisted over Lesotho and the southeastern coast of South Africa. The rainfall situation improved over Mozambique, Zimbabwe, Malawi and Zambia compared to the last ten days. In southern Africa, satellite rainfall estimates indicated moderate rains over northern and western Zambia, southern Zimbabwe, central and northeastern Angola, most of Botswana, western Madagascar and pockets in Mozambique.
November 21, 2001

Most oceanic and atmospheric indices reflect ENSO-neutral conditions. However, there are indications of a slow evolution towards a warm episode. Since late June 2001 sea surface temperatures (SSTs) have become anomalously warm in the central equatorial Pacific, with anomalies near 1°C just to the west of the date line. During the same period, subsurface temperature anomalies have remained positive in the central equatorial Pacific between 160°E and 120°W, indicating a deeper-than-normal thermocline in that region. This pattern has been observed immediately prior to the onset of past warm episodes. The latest statistical and coupled model predictions indicate either weak warm or near-normal conditions in the equatorial Pacific during the remainder of 2001 and into the first half of 2002. However, all of these prediction techniques have difficulty in making skillful forecasts during ENSO transitions. Considering the SST predictions, the time of year, and the observed oceanic and atmospheric circulation patterns, it seems most likely that a gradual evolution to warm episode conditions will continue in the tropical Pacific over the next several months. For the weather features this week, we point out the continued substantial rainfall occurring in southern Africa. As noted last week, the prediction for Dec-Jan-Feb 2001-2002 southern Africa rainfall at one month lead calls for climatology across much of southern Africa with slightly higher than climatological probabilities for above normal rainfall predicted for northeastern southern Africa, including northern Mozambique, Malawi, and southern Tanzania.
November 28, 2001

With the formation of several tropical cyclone systems in the South Indian, for this preamble we update the observed sea surface temperature as this is a major factor in cyclone development. Within sst.gif we see that the South Indian Ocean for the period November 18-24 has cooled somewhat from earlier in the season and the temperatures are generally near neutral with some areas remaining about 0.5-1.5 degrees above the 1961-1990 average. These sea surface temperature products are updated weekly by the NCEP/Environmental Modeling Center and are found at the web site: http://www.emc.ncep.noaa.gov/research/cmb/sst_analysis/images/oisst.gif For the weather features this week, we point out the continued substantial rainfall occurring in the band from Zaire, Congo and Gabon southeastward toward mid-southern Mozambique and northern South Africa.
December 6, 2001

We note that last year the first named cyclone in the South Indian Ocean did not occur until early January whereas this year we have already had two named cyclones. As was stated last week, the sea surface temperatures in the Indian Ocean are generally near neutral with some areas remaining about 0.5-1.5 degrees above the 1961-1990 average. We continue to monitor the situation and will appraise people of possible landfall. Moderate to heavy rains continued in pockets of eastern Kenya and southern Somalia, while dryness continued to prevail over much of Tanzania. Wet conditions remained across much of southern Africa, with the heaviest rains located in Angola, Botswana, and southern Mozambique. Dryness, however, continued over northern Mozambique. In central Africa, Gabon, Congo, and DRC recorded heaviest amounts of precipitation. EDITORIAL NOTE: During this first year of producing the Africa Threats Assessment we have had a continuing internal discussion concerning the issuance of "threat" notices in areas that are receiving heavy rains that are "near-normal". The concern is that we should focus on perceived "true" threats and not overemphasize a position where a routine statement can be made. For example, we have discontinued the threat of heavy rain over Madagascar this week though the rains appear likely to continue. You are the users of the product and we offer you the opportunity to weigh-in on the issue. If you have any thoughts or concerns please send them to Alvin.Miller@noaa.gov
December 13, 2001

At this start of the cyclone season in the South Indian Ocean, we have added information to the CPC USAID/FEWS web site to aid your understanding of the current cyclone situation. Under the URL http://www.cpc.ncep.noaa.gov/products/fews/ there exists an additional category of Cyclone Monitoring; Indian Ocean. It consists of a 24-hour false-color infrared imagery loop of the Indian Ocean, a map of the 700 mb winds, and a current cyclone track image from the University of Hawaii. Concerning the latter, we are investigating ways to implement our own position graphic with forecast positions included. Satellite imagery depicted a large thunderstorm complex over southern Mozambique and adjacent parts of South Africa, Zimbabwe, and Swaziland on December 11. This moisture comes on top of ground already wet from persistent above-normal rainfall since October. Four-week rainfall has totaled more than 200 percent of normal across much of southern Africa, including Botswana, southern Zimbabwe, central and eastern South Africa, and extreme southern Mozambique. Rainfall totals for the week ending December 10 ranged from 30 to 100 mm in a band stretching from southern Mozambique northwestward through Zimbabwe, Zambia, Angola, into DRC. To the northeast, the area that has seen persistent dryness since October, including eastern Tanzania and northern Mozambique, measured 5 to 30 mm in the past week. This is not enough rainfall to significantly relieve dryness, but the increased shower activity may be a sign that the rainy season is finally beginning.
December 20, 2001

Heavy showers on December 10-11 contributed to flooding in northeastern South Africa and southern Mozambique, but rainfall has since diminished in both areas as the axis of heaviest rains has shifted northward. Heavy showers have moved into the dry areas of northern Mozambique, but amounts remained relatively light (1-25 mm) over extreme northern Mozambique this past week. Overall conditions remained abnormally wet from Zambia southward to South Africa and eastward through southern Mozambique, with many stations recording over twice their normal rainfall totals in the past 4 weeks. Showers (1-25 mm) eased drought over eastern Tanzania, but much more rain is needed to make an appreciable dent in the deficits that have been accumulating since October. Showers also eased dryness in eastern and northern Kenya, where long-term drought persisted in the north. On a more positive note, the sea surface temperatures in the eastern portion of the South Indian Ocean have cooled considerably over the past several weeks. This has been accompanied by a lack of cyclone development in the area.
December 27, 2001

Most oceanic and atmospheric indices reflect a continuation of ENSO-neutral conditions. However, there are indications of a slow evolution towards a warm episode. Since late June 2001 sea surface temperatures (SSTs) have become anomalously warm in the central equatorial Pacific, with anomalies near 1 Degree C just to the west of the dateline. During the same period, subsurface temperature anomalies have remained positive in the central equatorial Pacific between 160E and 120W indicating a deeper-than-normal thermocline in that region. Similar patterns have been observed immediately prior to the onset of previous warm episodes. The majority of the latest statistical and coupled model predictions indicate near-normal conditions in the equatorial Pacific during the next three to six months. However, all of these prediction techniques have difficulty in making skillful forecasts during ENSO transitions. Considering the time of year, and the observed oceanic and atmospheric circulation patterns, it seems most likely that a gradual evolution to warm episode conditions will continue in the tropical Pacific over the next several months. Heavy rains moved northward into central and northern Mozambique during the period from December 18-24, as precipitation totals exceeded 100 mm locally with widespread amounts greater than 50 mm throughout the region. Although southern Mozambique dried out somewhat, coastal areas of southeastern South Africa received rains totaling 100 mm, while further inland amounts were generally less than 50 mm. The heaviest showers in central Africa were confined to central DRC where scattered satellite estimated rainfall totals topped the 100 mm mark. As opposed to previous months, the region surrounding Gabon accumulated much less rainfall during the past week, with totals generally less than 25 mm, except in northern Congo where rains exceeded 50 mm locally. Rains diminished in coverage throughout southern Somalia and eastern Kenya, although pockets of heavy rainfall were recorded east of Nairobi. Precipitation throughout much of northern Morocco was the heaviest of the season, with rainfall totals greater than 100 mm recorded. Although some relief occurred in northern areas, most of the rain did not fall in the central and southern dryness affected region of the country.

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